Maximum-demand indicator.



J. T. EEECHLYN.

MAXIMUM DEMAND INDSCATOH.

APPLICATION FILED Kim/.11. 19:3.

Paten fied fiept. 4, 191?.

Inventor: John T. Beechlgn,

Witnesses 44% if"; f

tion.

UNITED STATES PATENT OFFICE.

JOHN '1'. IBEECHLYN, OF LYNN, MASSACHUSETTS, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK. 1

MAXIMUM-DEMAN D INDICATOR.

Application filed November 11, 1913.

To all whom it may concern:

Be it known that I, JOHN T. BEECHLYN, a citizen of the United States, residing at Lynn, county of Essex, State of Massachusetts, have invented new and useful Tmprovements in Maximum-Demand Indicators, of which the following is a specification. 1

Nly invention relates to maximum demand indicators and in particular to maximum demand indicators of that general type described in the Letters Patent of Lewis T. Robinson, No. 1,118,444, patented'November 24, 1914..

The maximum demand indicator described in the above identified patent comprises broadly a movable member actuated by the rotatable shaft of an electric' meter element and adapted to be periodically returned to an initial position, when the member has been moved from such initial position a distance which is substantially a measure of the instantaneous rate of con sumption of energy in an electrical installa- In substance, this instrument measures the demand as the representative average rate of consumption of energy during each of a number of time intervals and indicates the maximum measurement. When the consumption of energy in the installation is interrupted the rate of consumption of energy is obviously reduced to zero, and in the type of indicator described in the above identified application the movable member is returned to its initial position. Usually the interruption of the consumption of energy will take place during the interval of measurement of "the demand and not at the exact end of any such interval of measurement. The interval of measurement is thus .only partially completed When the return of the movable member to its'initial position terminates the measurement of the demand for this partial interval, and thus gives a measurement of the demand which is smaller than the actual demand during such partial interval.

The error occasioned in the measurement of the demand by the interruption of the consumption of energy before the time inter- .va-l'for the measurement of the demand has terminated is, of course, in favor of the consumer since it represents a' smaller demand than actually existed. While this Specification of Letters Patent.

7 Patented Sept d, 1917.

Serial No. 800,300.

breakers in the installation during the inter:

val of measurement of thisexcessive demand with the result that the measured demand for this intervalis much less than the actual demand. Again, an unscrupulous consumer can defeat the purposes of a maximum demand indicator by interrupting the consumption'of energy in his installation during each interval or period of the measurement of his demand. Other instances in which the interruption of the consumption of energy interfers with the measurement of the demand to the prejudice. of the central station management will be apparent to those skilled in the art.

The erroneous measurement of the demand of an. electrical installation occasioned by the interruption of the consumption of energy during the interval or period of measurement is not only characteristic of that type of maximum demand indicator described in the aforementioned patent but is also characteristic of all other types of maximum demand instruments with which I am familiar. An objectof my present invention isv to provide a maximum demand indicator Whichdoes not possess this object-ionable characteristicf l, accordingly, aim by the present invention to provide a maximum demand indicator in which the movable member is maintained in the position to Which it has been moved when the consumption of energy in the installation is interrupted, and is not returned to its initial position until the interval of measurement is fully completed after the consumption of energy has been resumed. In such an D obvious that the same consrclen. ions of J. .3 1; ,i1,,'i. as c i teiial one rapid ienection 1 rate or CODSUliTilOil OI ample, a "cry so lden subs! duction in the rate of consumption o has 2, similar tendency to produce measurement of the demand as in the case of the complete interupticn of tie consumption of energy. of convenience in explaining 3I1J l1i\-ll3l01i have employed the expresl n intei iption of the consumption or" energy throir t the sgs'c 'cificationandrclaiins of this application, but it will be nnclerstood that i ii'ioencl this cxpresion to cover l and rapid reduction of the rateof the consu ticn energy as well as a reduction of the of consumption of energy t osere.

Another object of my present invention is to provide a novel and improved arrange- .inent of'inechanical elements for sheeting the reto of the movable rnoniher to its osition, in the type oi ins inane indicator described in tn afforeone. patent of Lewis T. Robinson and patent of the se No. l0, patented llo 7. J Further y of my piesent in evidencec in the course er the following clescripticn.

mum rleapps i, hereto. i is construction niocle ci 0 eration of a maximum demand indicator embodying the novel features of my invention Will be understood from the following description taken in connection with the accompanying rawings in which Figure l is a diegrammsticyiew in perspective of a maximum demand indicator embodying the features of my present inention; and. Figs. 2 and 3 are vie s illustreting certain details of construction.

Referring to Fig. 1 of the drawings, there is shown an electrical installation comprising conductors} supplying electric energy to translating devices (3. A Watthour meter of the induction type is operativcly connected in the installation in the usual manner for the purpose of integrating ancl recording the total quantity of energy eonsuinecl in the translating devices. The incluction Wattmeter comprises the usual series coil 7 and the potential coils 8 Which produce a. rotary magnetic field propon tioiial to the instantaneous rate of consumption of energy in the Well understood men in c of shaft 22 is resiliently o) 'fl 1 I J. sociniecl w 36 member i 9 l (:1.

rigidly secured to 5" spring 1" e end to t l ure of the sti and a mess oi consn' opc'on or" ene devices 0 .E-he instalh tial position of the elmeet is determined ti 1.3 111d co sto 22 is pivot catcd nuns l i; the member of a leaf spring which to the member 2i and i end a flattened surface 1\ .Jsse l o.-.' shaft This construction W' clerstoocl by reference to Fig.

ings. in 0 set pin is rigicly scour '11; the shaft oppos'ze the of the slow The pin thus moves in sponse to oreioents oil the indi a meter armature 11, and in addition is table disk 9 of the We The shaft 25 Qsni-c is it A movable member 28, in the form'of a counterweightedi cross arm, carries at one extreme end an arm or pawl member 29. The pawl member 29 is adapted to engage in the teeth of the gear 27 and in conjunction with this gear it thus constitutes a driving connection between the rotatable shaft 25 andthe movable member 28.

A spring 30 is operatively connected to the movable member 28 and tends to maintain this member in an initial or zero position and to return the member to such position whenever the driving connection between the rotatable shaft 25 and the member is interrupted. The initial or zero position of the member 28 is determined by the engagement of the pawl member 29 with-a fixed stop 31, which is best shown in Fig. 2 of the drawings.

The movable member 28 is rigidly secured to a pivoted shaft 32, and, as heretofore mentioned, is provided at one end with a counterweight 33. The other end of the movable member 28 is bent, as will be best seen in {Fig 2 of the drawings. A shaft 34: is rotatably mounted in a boss 35 rigidly secured at the elbow of the bend in the movable mem ber 28. A pinion 36 is rigidly secured to the shaft 34' and meshes with a stationary gear segment 37. A ratchet or star wheel 38 is also rigidly secured to the shaft 34. A planetary motion is thus imparted to the pinion 36 and ratchet wheel38 by a movement of the movable member 28.

The pawl member 29 is secured to the extreme end of the bent portion of the movable member 28 by meansof a balanced disk segment 39, the disk segment being pivoted to the movable member 28. A trip lever 40'. is also secured to the disk segment 39, and wheh depressed operates to raise the pawl member 29 out of engagement with the teeth of the gear 27. A leaf spring 41 is operatively connected between the disk segment 39' aud t-he boss 35 and serves -by its tension to keepthe pawl member 29 out of engagement with the teeth of the ear 27. If, however, the pawl member-is already in engagement with the teeth of the gear 27 the friction between the pawl member and the teeth of the'gear, due to the tendency of the movable member to normally return to its initial position, is sufficiently great to overcome the tension of the spring 41 and the pawl member will thus remain in engagement with the teeth of the gear 27 until this engagement is interrupted by a depression of the trip lever 40.

' The remaining details of construction and arrangement of the varidus elements in my novel maximum demand indicator will be best understood-froma description of the operation thereof. When energy is being consumed in'the translating devices 6 the disk armature 11 of the indicating wattmete'r element and also the pin 24 will assume a position which is always a measure of the instan- Y the member 28 and meshing with the stationary gear segment 37 has a planetary motion which is similarly imparted to the ratchet wheel 38. That is, the pinion 36 and ratchet wheel 38 are simultaneouslyrotated about the axis of the shaft 34 and also about the axis of the shaft 32.

The ratchet wheel 38 in advancing clockwise with a planetary motion eventually overtakes the pin 24, whereupon the pin engages in the teeth of the ratchet wheel. The

paths of movement of the pin 24 and of the ratchet wheel 38 are coincident so that the pin always intercepts the movement of the ratchet wheel. Further progress- ,of the ratchet wheel due to the continued rotation of the shaft 25, results in the radial depression of the pin 24 until it descends upon the tripTever 40. The engagement of the pin 24 with the trip lever l0 moves the pawl member 29 out of engagement with the gear 27 and permits the movable member 28 to return toits initial position by the action of the spring 30, which has a certain amount of initial tension. When the pawl member 29 in its return motion strikes the flattened surface gagement with the teeth of the gear 27 whereupon the cycle of operations just described is repeated When the return sway of the movable member 28 begins the pin 24 is immediately liberated by the reversed rotation of the: ratchet wheel 38.

properly balanced, will by its own inertia The pawl member, if

keep out of engagement with the teeth of gear 27 during the return sway, I prefer, however, to employ a very light spring acting near the fulcrum of the pivoted pawl member, such as the spring ll hereintofore described, forassistingf in maintaining the pawl member disengagid from the teeth of the gear 27 until reset and retained by the action of the stronger spring 30.

The pawl member extends some distance beyond the gear 27 and is adapted to engage with an arm 42. connected, by means of a coil spring 43, with one end of a counterweighted cross arm 44. An indicating member, such as the,pointer 45, is secured to the cross arm 44 and is arranged to sweep across a suitable scale 46. The cross arm A is spring pressed in the usual manner so that the pointer 45 is resiliently non-returnable, and will thus re of the stop 31 it is forced into operative en:

The arm 42 is resiliently Y table shaft when the demand made by Said installation upon its source of electric energy supply becomes zero regardless of the length of time such demand remains zero.

4. A maximum demand indicator com-' prising in combination a watthour meter having a rotatable shaft, a movable member having aninitial position and adapted to be operatively connected to said rotatable shaft, means for returning said movable member to its initial position when it has been moved from its initial position a distance which is substantially a measure of the rate of consumption of energy in an electrical installation, and means included in said first mentioned means for preventing the return of the movable member to its initial position when the demand of the installation upon its source of electric energy supply becomes zero provided the distance the movable member has moved from its initial position is insufiicient to be substantially a measure of the rate of consumption of energy at the instant before the demand of the installation becomes zero.

5. A maximum demand indicator comprising in combination a movable member having an initial position, means for moving said member, means for returning said member to its initial position when the distance the member has moved from its initial a position is substantially a measure of the rate of consumption of energy in an electrical installation, means for preventing the return of the movable member to its initial position when the consumption-of energy in the installationis interrupted provided the distance the movable member has moved from i s initial position when the energy consumption is interrupted is insufficient to be substantially a measure of the rate of consumption of energy at that lnstant, and means lncluded in said last mcnti oned means whereby the movable member must be forwardly moved a predetermined minimum distance after any interruption of the energy consumption before said member can be returned to its initial position.

G, A maximum"demand indicator comprising in combination a movable member 'having an initial position, means for moving said member, means for returning said member to its initial position when the distance the member has moved from its initial position is substantially a measure of the rate of consumption of energy in an electrical installation, means included in said last mentioned means whereby said movable member is maintained in the position to which it has been moved when the demand of the installation upon its source of electric energy, supply is interrupted and until the installation again makes a demand upon its source regardless of the length of time the prising in combination a watthour meter element having a; rotatable shaft, a movable ber, and means whereby said movable member, is maintained in the position to which it has been moved when the-demand of the installation upon'its source of electric energy supply is interrupted and is not returned to its initial position'until the'distance of the member from its initial position is substantially a measure of the rate of consumption of energy after the installation again makes a demand upon its source.

8. A maximum demand indicator commember adapted to be. operatively connected to said rotatable shaft, a wattmete'relement, a pin operatively related to said wattmeter element, a ratchet. wheel, said pin and said ratchet wheel being arranged for relative movement in. a coincident path, means whereby the operative connection between said rotatable shaft and said movable member is interruptedand the movable member is returned to an initial position when said pin engages with said ratchet wheel, and

for indicating the maximum move ment of said movable member.

9. A, maximum demand indicator comprising in combination a watthour meter element having a rotatable shaft, a movable member adapted to be operatively connected to said rotatable shaft, a ratchet wheel adapted to be rotated by said rotatable shaft, means controlled by awa'ttmeter element for moving a pin into engagement with the teeth of said ratchet wheel whereby further rotation of said ratchet wheel by said rotatable shaft interrupts the operative connection of said movable member with said rotatable shaft, means for returning said movable member to an initial position when the operative connection between the member and the shaft is interrupted, and means for indicating the maximum movement of said movable member.

10. A maximum demand indicator comprising in combination a watthour meter element having a rotatable shaft, a movable member having an initial position, a driving connection between said rotatable shaft and said movable member, a ratchet wheel operatively related to said driving connection and adapted tointerrupt said driving 55111 dam Gill of consumption 0L5 energy in alas-trim} instaliatiem a pin operatively connected t0 said indicating Wattmeter element and having path of mevement coincident v: with the path of msvemeniznf Saki ratch t, W11 e1, means whereby the engagement of whet whei Wiilil said pin intei'mpim .lng connec'ion between said Tom 'hafi. and said movable member, means 5 turning said movable member to pos't-ien when the driving connection the member and the shaft is inter rupted, and means for indicating the ma mum movement of said mevabie member. 13. A maximum dfimand indicaim c0m-' prising in cembinzition an electric mam fla mam; havi g" a mtatablz Sim t, a ms'v'aijis the rate d means 11.

0n 0; file renal o e sqd member can wositinn, movable memaf' 2-, tripping hevice adiapteci yely disconnect said member from said shaf t, means positively actnateciby the rotation of said shaft for operating said} nipping device, and means for returning said Inc-Yams member so ii s initial @GSiiiifiiE Each V said. device is 0' lei 

